<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box1{
            position: relative;
            width:800px;
            height:400px;
            border:2px solid red;
            background-color: yellow;
            margin-top:200px;
            margin-left:200px;
        }
        .box2{
            position: absolute;
            left:50%;
            top:50%;
            margin-left:-150px;
            margin-top:-50px;
            width:300px;
            height:100px;
            border:2px solid red;
            background-color:skyblue;

        }
        .box3{
            width:800px;
            height:400px;
            background-color:red;
            border:1px solid skyblue;
            margin-left:200px;
            margin-top:100px;

        }
        .box4{
            width:200px;
            height:50px;
            margin:175px auto;
            background-color:yellowgreen;
        }
        .box5{
            width:800px;
            height:400px;
            background-color:chartreuse;
            border:1px solid skyblue;
            margin-left:200px;
            margin-top:100px;
        }
        .box6{
            width:200px;
            height:50px;
            background-color:black;
            transform: translate(150%);
            margin:175px 0;
           
        }
     
    </style>
</head>
<body>
    <div class="box1">
        <div class="box2"></div>
    </div>
    <div class="box3">
        <div class="box4"></div>
    </div>
    <div class="box5">
        <div class="box6"></div>
    </div>
</body>
</html>